Aluminum 302

[Jac Mac]

Just in case anyone has misunderstood my previous posts..
With regard to your engine build if I could lighten a car by say 30/40 kg by using an alloy block/lighter wheels etc I would do that and then try to go a little more conservative on the engine build...lower compression, less aggressive cam... still retain a light crank/rod/piston package..... with that type of thinking your setup should last for several years, as long as you dont skimp on the maintanance, go looking for trouble, because if you dont it will find you..

 

[Sean]

Just in case anyone has misunderstood my previous posts..
With regard to your engine build if I could lighten a car by say 30/40 kg by using an alloy block/lighter wheels etc I would do that and then try to go a little more conservative on the engine build...lower compression, less aggressive cam... still retain a light crank/rod/piston package..... with that type of thinking your setup should last for several years, as long as you dont skimp on the maintanance, go looking for trouble, because if you dont it will find you..

So where do you sit on the hydraulics vs solids debate. Seems like the only drawback to solids is setting the lash on occasion.

 

[Sean]

Jac hit on something about building it strong from the start. Open track cars usually will be used for many years. Racecars usually (broad term) are competitive for much shorter timeframes and then are retired. Parts that wear or fatigue on them are replaced on a time in useage schedule. Some of this is to prevent DNF's and increase safety margins for a car that is driven at the limit for much longer periods but both of these considerations seldom apply to a fun day track car.

The open track car on the other hand can remain fun enough for many years, even decades. So what am I getting to. Adding weight may be in your long term interest, at least as far as increased reliability/life cycle is concerned. For instance when making upper a arms for my GT40 I decided to use a heavier wall thickness instead of just thick enough because I didn't want to make more later or be concerned about failure (pot holes again). Think about at least building it a bit stronger than you think it requires. A few more pounds if used correctly can make your car a lot longer lived. Sort of endurance racing instead of sprints.

If you look at bodywork for example. Super thin fiberglass body panels are a lot lighter but will crack with the first pothole. How many engine covers do you want to buy over the life of your car? Same thinking with a lot of this stuff like a pump gas 6K RPM motor instead of a race gas motor run up to 8K+. Same fun more or less at the track but a lot less maintance and $$$$$'s.

In the end, it's your car and your money, you should do what makes your panties wet. IMHO while you are in the planning phase, spend a little time thinking through what you really want when it comes to really high dollar race parts. Like the man said. How fast do you want to go?

Just something to think about. Smart move by the way, asking these questons before you start spending money. Ask away, thats what this website is for.

Other than changes like fuel cells and the shock/spring/bar upgrades everything will be pretty much standard SPF fare. I trust that is going to be strong enough?

On the motor front maybe my internal spec is a little overkill, but on that count it should be crisp and last. Since I have no actualy xperienc maybe 6k rpm is fine, but the current plan is to do a sold lifter motor that can run out to 7k or above as need be, on pump gas.

More revs means more valvetrain wear and I suppose piston wear in the bore. Frankly if a trackday car can go 10-15k before motor refresh I will be happy.

My limited understanding is that a solid roller motor can be stroger everythwere including lower revs, but its a big internal mental debate because its more maintanance.

 

[Darrin]

Sean, is there a reason you just don't go with a Coyote based 5.0 seeing that you want it to rev so high and not require much maintenance?

The price for a Ford crate engine with PCM is only about 8K for a Coyote and you can upgrade to the Aluminator version for about 1K more. If you want to make more serious power, several builders offer CNC head porting and stronger cams that push the Aluminator well over 600HP at the flywheel. One package I am looking at is about 12K (although I will be supplying my own Cobra Jet intake...add another 1.5K for that).

You will be hard pressed to build a more reliable engine that strong for the cost if you are looking to buy an aluminum block to build upon.

Just a thought.

 

[Sean]

Sean, is there a reason you just don't go with a Coyote based 5.0 seeing that you want it to rev so high and not require much maintenance?

The price for a Ford crate engine with PCM is only about 8K for a Coyote and you can upgrade to the Aluminator version for about 1K more. You will be hard pressed to build a more reliable engine that strong for the cost if you are looking to buy an aluminum block.

Just a thought.

Coyote is not orgional to the car, is heavy and bulky. Easier to go with a 351 bsed 427 than a coyote, I think even that is lighter. But yeah maintanance wise a coyote is far easier.

 

[Darrin]

Coyote is not orgional to the car, is heavy and bulky. Easier to go with a 351 bsed 427 than a coyote, I think even that is lighter. But yeah maintanance wise a coyote is far easier.

Actually:

1) A stroked and bored 351 wasn't original to the car either
2) The Coyote weighs LESS than a Ford 351W (the whole thing is only about 430lbs for the Coyote, but around 500lbs for a 351)

The Coyote is a bit bigger though in that the engine is wider for sure, but it will fit in the GT40 (many of us are doing and have done, just that).

I understand if you just want to say "It's a 427" though.

 

[Jac Mac]

So where do you sit on the hydraulics vs solids debate. Seems like the only drawback to solids is setting the lash on occasion.

Solids for me, I dont see the lash setting as a drawback at all, its a key element to knowing the condition of your valvetrain, If your checking regularly you should catch stuff/wear etc before it becomes a major problem....if you go hydraulic & adopt an attitude that you dont need to check it the damage issue will have become major by the time the lifter travel has been exceeded & the warnings signs appear- noise, misfiring, smoke etc.. BTW I have yet to meet the perfect driver who never exceeds the limits imposed by a hydraulic valvetrain, even with a rev limiter! On a wet track with a boot full of throttle, most if not all of these engines will exceed the rev limiter, sure the limiter cuts in & you hear the misfire, but often the engine is accelerating so quickly that it carries on up past the limit, exceeds the spring capability & your in valve to piston contact land..
If your not doing regular leak down tests along with valve lash you wont find it til too late..

 

[Sean]

Actually:

1) A stroked and bored 351 wasn't original to the car either
2) The Coyote weighs LESS than a Ford 351W (the whole thing is only about 430lbs for the Coyote, but around 500lbs for a 351)

The Coyote is a bit bigger though in that the engine is wider for sure, but it will fit in the GT40 (many of us are doing and have done, just that).

I understand if you just want to say "It's a 427" though.

Yeah but I am going for a 302 which will be at least 100lbs less.
Plus with a 302 you can vintage race. So no 427 for me either way.

 

[Sean]

Solids for me, I dont see the lash setting as a drawback at all, its a key element to knowing the condition of your valvetrain, If your checking regularly you should catch stuff/wear etc before it becomes a major problem....if you go hydraulic & adopt an attitude that you dont need to check it the damage issue will have become major by the time the lifter travel has been exceeded & the warnings signs appear- noise, misfiring, smoke etc.. BTW I have yet to meet the perfect driver who never exceeds the limits imposed by a hydraulic valvetrain, even with a rev limiter! On a wet track with a boot full of throttle, most if not all of these engines will exceed the rev limiter, sure the limiter cuts in & you hear the misfire, but often the engine is accelerating so quickly that it carries on up past the limit, exceeds the spring capability & your in valve to piston contact land..
If your not doing regular leak down tests along with valve lash you wont find it til too late..

Thanks, reinforces my thinking.

 

[Darrin]

Yeah but I am going for a 302 which will be at least 100lbs less.
Plus with a 302 you can vintage race. So no 427 for me either way.

A Ford 302 weighs about 450lbs although you can save a few with aluminum heads and intake though. It's not all that much lighter than a 351W. Only 50 or 60 pounds less. Just something to think about for your build.

 

[Sean]

A Ford 302 weighs about 450lbs although you can save a few with aluminum heads and intake though. It's not all that much lighter than a 351W. Only 50 or 60 pounds less. Just something to think about for your build.

From what I see more like 80 lbs lighter if you include the lighter internal rotational mass, most importanlty most of the weight is lost from the top. With Aluminum heads you go beolw 400 lbs and into the mid 300's with aluminum block. The 8.2 block also has the weight savings off the top of the block where it seriously helps.

I agree that for a road car the 351 based motors are ideal. They are stronger and will make more torque at lower revs than a 302 based motor.

On track all that extra power is going to be unuseable unless you have serious straights, the 351 motor will wreak havoc with tranny and halfshafs and the weight will work against you in corners and braking. For the types of tracks we have int he USA I dont see a 351 motor offering a performance advantage and there are some significant disadvanatges. On the open road with big straights no 302 will touch a 351 based motor.

The 302 motor is going to be more stressed and will have to spin higher to make the power, reducing potential engine life. But I think any track motor has a reduced life anyway, and you can compensate by building them pretty strong.

So yes a 302 motor will cost 16k to make reliably slightly less power as a 12k 351 based motor. On a road course I think a 500 hp 302 based motor will already be overkill. But I can see how the strength and reliability of a 351 is compelling pretty much everywhere else..

 

[Mike]

On track all that extra power is going to be unuseable unless you have serious straights, the 351 motor will wreak havoc with tranny and halfshafs and the weight will work against you in corners and braking. For the types of tracks we have int he USA I dont see a 351 motor offering a performance advantage and there are some significant disadvanatges.

Is this why Olthoff runs a 427W and from what I understand the other car that was a 302 is also now running a W? I enjoy your threads and the conversation but you strike me as someone inflicted with paralysis by analysis. Have you ordered a chassis yet?

 

[Rich E.]

Is this why Olthoff runs a 427W and from what I understand the other car that was a 302 is also now running a W? I enjoy your threads and the conversation but you strike me as someone inflicted with paralysis by analysis. Have you ordered a chassis yet?

Bingo!

 

[Robert May Eng.]

Guilty as charged You cant blame someone for wanting the best of everything in their build and this is the best place to bounce ideas about to achieve exactly that.

Bob

 

[Keith]

Bench racing is an honoured tradition. I am sure that 90% of builders do it anyway some on here, some on the phone to by email, and many (like me) in my local hot rod shop every Saturday.

Unseen others are also learning from Sean's research and reasoning (including me) Let it continue please smug people.

 

[Mike]

Afflicted not inflicted. Never said that anyone should not want the best of everything and bounce ideas around in that pursuit. In the example I pointed out the author made an assertion that is direct contradiction to one of the leading racers of GT40s in the world. Based on what? When the conversations hinges on ideas like a Windsor is more top heavy than a 302 and as such will raise the CG enough to affect handling... Get on with it already!

 

[Mike]

Bench racing is an honoured tradition. I am sure that 90% of builders do it anyway some on here, some on the phone to by email, and many (like me) in my local hot rod shop every Saturday.

Unseen others are also learning from Sean's research and reasoning (including me) Let it continue please smug people.

Have you learned 427W's wreak havoc on halfshafts because someone who doesn't own one said so even when Olthoff runs 427s in both cars? What else have you learned?

 

[Keith]

There are many questions and even more answers Grasshopper.

The path to Wisdom is choosing the Right Answer - for You.

Sean is at least applying some wisdom to the type of racing he intends, smaller tighter tracks etc. Personally, he sounds very European in his outlook.

"Build it stiff, and add lightness"

It was always the contention of the European Gt40 race teams that the 5 litre was good enough to win if they developed it more - a philosophy they went on to prove with 2 year consecutive wins following Ford's departure with a 4.9 litre engine with alloy Westlake heads.

It is also a fact that the biggest mechanical let down of the MK1 program (apart from the early Colotti) was the 289 head gaskets which the UK teams 'fixed' with Cooper Rings following Ford's quite inexplicable refusal to modify the top end. There is no doubt whatsoever, that a 289 powered car could have won Le Mans much earlier, if it hadn't have been for the committee style management.

By the by, Sean's philosophy is in line with that of the original thinkers and I find it interesting for an American to follow that route.

Anyway, I apologise for intervening, I'm sure he can speak for himself, if he is allowed to that is

 

[Sean]

Have you learned 427W's wreak havoc on halfshafts because someone who doesn't own one said so even when Olthoff runs 427s in both cars? What else have you learned?

Since you ask. Olthof told me he could run a 427 in his car because it was a Mk2 and early days, that a Mk1 cannot run a 351 block in historics. The other Mk1s are all running 302 blocks that race and Olthoff has not put his 427 back together.

Olthof also told me that If I was going to be running track almost exclusively the torque of the 427 would wreak havoc with halshafts Cv joints. Fine for the street different for the track. So from a drivetrain perspective a 302 based car is going to last.

I have also heard from same and similar sources that there is a noticeable difefrence in terms of handling with the top weight of a 351 block. Ie there is about 1.3 inches more hgeight and 80 or so lbs in that height, where it is least desireable. Internal rotational mass is more.

Yes a worked 351 powered car is going to be faster to a point, more Hp will sort of do that.

I seriously doubt that most drivers below the leverel of Olthoff can really exploit the extra power that a 351 based motor can put out on track. The hard track driven amateur cars seem to be in the 400's hp range.

The limitations of a 302 are weaker block, which is cured with aftermarket blocks, and the need to spin them to make power, which requires stronger and more expensive internals. It also means you end up with a more racy motor for your track car.

So yes for a street driven car there is no doubt that a 351 is the way to go. More reliable power, less expensive. On the track, and most tracks are not lemans, something that can brake and turn better may well be more rewarding to drive and you may well go faster.

The question to me is it worth going further with an aluminum block, and will this greater loss of weigth affect known chassis setups.

Simply put, you cant race a mk1 with a 351 motor, and with todays tech a fully worked 302 may be quciker on track, and will certainly lead to a longer lived drivetrain with a more "authentic to Mk1" sound and rev range.

The motor specs for me look something like 530 hp at 7200 rom and about 470 ftlbs of torque. So this is less than a 427 and you need to spin it more.

 

[Glenn B.]

Just a minor historical correction here: The Europeans didn't switch back to the small block in 1968 because they had a better engineering idea. The rules were changed and the big motors were outlawed after the two Ford Big Block wins in 1966 and 1967. It wasn't a matter of innovation. They had no choice.

In reading driver comparisons of the Mark I and Mark II cars, the Mark II was felt to be much easier to drive fast due to the torque curve and overall horsepower. The numbers speak for themselves:

LeMans 1966 Big Block: Winner total distance 4,843 km
Average speed 210.795 kmph

LeMans 1968 Small Block Winner total distance 4,453 km
Average speed 185.536 kmph

I get just as much fun, speed and excitement out of my 611hp/605ft lb FE motor with the accelerator at 3/4ths as a 302 will wound out to the maximum. I shift fewer times, can short shift easily which results in less stress on my engine internals.

Before you dismiss this fact, consider that in 1968, when the 5 liter small block won, the competition was:

2nd place - Porsche 907 - 2 liter
3rd place - Porsche 908 - 3 liter
4th place - Alpha Romeo - 2 liter
5th place - Alpha Romeo - 2 liter
6th place - Alpha Romeo - 2 liter

So, even in 1968, the "Big Block" 5 liter won. Even today Audi dominates with their turbo diesels and hybrids. Reading their driver impressions brings you back to same fact Ford discovered in 1966...the ease of driving a car fast with a large and long torque curve. Interesting that the output of the new Audi diesel engines (since 2006) put out numbers more like the 1966 MKIIs: 550-650hp and 600-770 ft. lbs of torque at a 5,000 rpm red line.

You can't beat a big "torquer" for speed and durability...Ford (in the US) first proved that.